Thank you for contacting us.
Basically, the options you outlined (either the Fluent API and Visual Studio 2015, or an .rlinq file and Visual Studio 2012/2013) are the once available for the maintenance of the data access layer that consume Data Access. Our recommendation is to convert your .rlinq files to fluent models
and to use the latest version of Data Access.
Regarding Visual Studio 2015, currently, we are working on introducing official support about it in the NuGet packages
; the Visual Studio integration is not going to be extended in this direction, though.
I hope this helps. Let me know if you need further details.
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